# Set state to edit if not defined.
param(state)||param(name=>'state', value=>'edit');

if (param('state') eq 'edit')
{   # display the form
    print start_form('POST',self_url());
    # blah blah blah
    print submit('state','preview'), end_form();
} elsif (param('state' eq 'preview')
{   # display the results, prettily.
    print start_form('POST',self_url()),
          # A bunch of hidden fields to pass our data along
          hidden(parameter-n, value),
          # This button commits the data to a file.
          submit('state','commit'), 
          # This button returns to the edit form, to make changes.
          submit('state','edit'), 
          end_form();
} elsif ( param('state') eq 'commit')
{    # Save the file
     # Print some nice messages.
} else
{   # General purpose error.  You should never wind up here
    # Trap it just in case.
}

##</code><code>##

 # A sample here doc
print <<"END_OF_HTML";
Blah laalbalalsdfasdf
asdf
blaha
END_OF_HTML